CWEA Grade 1 Lab Analyst Practice Test 2026 – Complete Exam Prep

The recommended choice for collecting a chloride sample is a glass or plastic container with no preservative. This is important because chloride ions can be affected by various substances, which means that using a container without any preservatives minimizes the risk of contamination that could alter the sample's chloride levels. Preservatives may introduce compounds that either react with the chloride or interfere with the analytical methods used for measuring its concentration. Therefore, a clean, unpreserved container ensures that the sample integrity is maintained and that accurate results can be obtained once tested.

Utilizing glass or plastic is typically preferred because these materials do not react with chloride like some metal containers might. Moreover, they are inert and compatible with the nature of the sample being collected.